Morphological record of oxygenic photosynthesis in conical stromatolites.
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ABSTRACT:
SUBMITTER: Bosak T
PROVIDER: S-EPMC2708726 | biostudies-literature | 2009 Jul
REPOSITORIES: biostudies-literature
Publications
Morphological record of oxygenic photosynthesis in conical stromatolites.
Bosak Tanja T Liang Biqing B Sim Min Sub MS Petroff Alexander P AP
Proceedings of the National Academy of Sciences of the United States of America 20090629 27
Conical stromatolites are thought to be robust indicators of the presence of photosynthetic and phototactic microbes in aquatic environments as early as 3.5 billion years ago. However, phototaxis alone cannot explain the ubiquity of disrupted, curled, and contorted laminae in the crests of many Mesoproterozoic, Paleoproterozoic, and some Archean conical stromatolites. Here, we demonstrate that cyanobacterial production of oxygen in the tips of modern conical aggregates creates contorted laminae ...[more]
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